Affiliation: | (1) Arthritis Research UK Epidemiology Unit, University of Manchester, Manchester Academic Health Sciences Centre, Oxford Road, Manchester, M13 9PT, UK;(2) Department of Biostatistics, University of Liverpool, Brownlow Street, Liverpool, L69 3GS, UK;(3) Clinical Research Department, Manchester Royal Infirmary, Oxford Road, Manchester, M13 9WL, UK;(4) Norfolk Arthritis Register, Norfolk and Norwich University Hospital, Colney Lane, Norwich, NR2 3SR, UK |